The growth of InAs$_{x}$Sb$_{1-x}$ solid solutions on miscuted GaAs(001) substrates by molecular-beam epitaxy method

The influence of substrate misorientation degree on the composition and morphology of layers during molecular-beam epitaxy of InAs$_{x}$Sb$_{1-x}$ solid solutions on the GaAs surface was studied. The GaAs wafers with orientation (001), which were miscuted in the [110] direction by 0, 1, 2 and 5$^\circ$, were used as substrates. The growth of heterostructures was performed for temperatures of 310$^\circ$C and 380$^\circ$C (lower and upper boundaries for the temperature range of structurally perfect InAs$_{x}$Sb$_{1-x}$ films formation, respectively). The influence of the arsenic molecular form (As$_2$ or As$_4$) on the composition of layers was studied. Studies of composition and structural properties were carried out using high-resolution X-ray diffractometry (HRXRD) and atomic force microscopy (AFM). It was established that in the series of misorientation from 0 to 5$^\circ$ the arsenic fraction x increases consecutively with the use of both flux of As$_2$ and flux of As$_4$ molecules. When the flux of As$_2$ molecules is used, the fraction $x$ increases insignificantly (in 1.05 times) with a rise of misorientation degree, but when using As$_4$ molecules, $x$ increases in 1.75 times. The increase of the growth temperature leads to the rise of the arsenic fraction in the solid solution. The morphology of the surface improves during increasing of misorientation degree at a low growth temperature and degrades at high temperatures.